lumber creepy crawlies...

[Matthew Hills]

I recently cut up a walnut log that had some boring activity (believe these are termites -- would welcome confirmation)
I ended up scrapping the entire log, but for future reference, I was wondering if some of the lumber could be salvaged by selecting sections where there was no observed tunnels? Or is that just inviting trouble?

435683

[Steve Eure]

Can't tell what size those holes are in reference to the log size, but I had similar holes in some elm logs that were large white larvae that ended up being mole cricket larvae. The holes went all throughout the logs so I had to burn them. The holes were about 1/4" - 3/8" in diameter. Looks similar to your pictures.

[Peter Kuhlman]

Looks to me like carpenter bees have bored holes to pack with bugs for the egg they lay in there. Termite damage is quite different then that.

[Roger Feeley]

Dang, I hunted for two years to find 200bf of oak hat was full of holes.

[Dave Mount]

We don't have termites in northern MN, but we do have several insects whose larvae live in wood and create holes like that. My experience is that organisms large enough to create holes that large require a fair amount of moisture and won't live in dry wood. They do their damage in living and green dead logs. My understanding is that termites also require moisture, which is why you avoid termite damage by keeping a separation between wood and moist earth.

The "borers" that we have also have a preference for sapwood of most species, and it looks like that's where you're seeing these. Many don't work in heartwood, though some do (meaning if yours are restricted to sapwood, you can cut that off).

Powder post beetles are the ones I know of that can work in drier wood and can emerge from finished furniture. What you have is not powder post beetles, they are quite small (exit holes circa 1/16").

Heat will kill all wood pests. I forget how high you have to go, my memory it is in the 130-140 F range for a few hours, I'm sure you can Google it. That sounds kind of high, but you can achieve it with a temporary solar kiln arrangement. Or you can see if you can find a small local kiln that will dry the wood for you.

My advice is probably worth what you paid for it, but if the amount of damage done already doesn't prevent you from making use of it, I think you can manage the problem.

Best,

Dave